Liquid crystal display device having particular counter electrodes

ABSTRACT

A liquid crystal display device includes a first substrate. A second substrate is facing the first substrate. A liquid crystal layer is interposed between the first and second substrates. At least one pixel area is defined by a plurality of gate lines and a plurality of drain lines arranged in a matrix over the first substrate, wherein the plurality of gate lines are extending in a first direction, and the plurality of drain lines are extending in a second direction. A first electrode is assigned to the pixel area, wherein the first electrode is provided over the first substrate. A second electrode is assigned to the pixel area and is facing the first electrode, wherein the second electrode is provided over the first substrate and is transparent. The second electrode has a solid portion and a hollow portion. The hollow portion is superposed to at least a portion of the first electrode. An insulating layer is provided between the first and second electrodes.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is related to and claims priority from JapanesePatent Application No. 2000-003348, filed Jan. 12, 2000.

BACKGROUND OF THE INVENTION

The present invention relates to a liquid crystal display device and,more particularly, to a liquid crystal display device which is calledIn-Plane Switching Mode.

Liquid crystal display device which is called In-Plane Switching Modehas a construction in which a pixel electrode and a counter electrodewhich causes an electric field (an in-plane electric field) having acomponent parallel to transparent substrates to be generated between thecounter electrode and the pixel electrode are formed in each liquidcrystal-side pixel area of one of the transparent substrates disposed inopposition to each other with a liquid crystal interposed therebetween.

This type of liquid crystal display device is constructed so that theamount of light to be transmitted through the area between the pixelelectrode and the counter electrode is controlled by the driving of theliquid crystal to which the electric field is applied.

Such a liquid crystal display device is known as a type which issuperior in so-called viewing angle characteristics and enables adisplayed image to be unchanged even when its display surface isobserved from an oblique direction.

The pixel electrode and the counter electrode have so far been formed ofa metal layer which does not transmit light therethrough.

In recent years, a liquid crystal display device constructed in thefollowing manner has been known: a counter electrode made of atransparent electrode is formed over the entire area of a pixel areaexcept the periphery thereof, and strip-shaped pixel electrodes areformed on the counter electrode with an insulating film interposedtherebetween, in such a manner as to be extended in one direction and tobe juxtaposed in a direction traverse to the one direction.

The liquid crystal display device having this construction causes anin-plane electric field to be generated between each of the pixelelectrodes and the counter electrode, and is still superior in viewingangle characteristics and is greatly improved in aperture ratio.

Incidentally, this art is described, for example, in SID (Society forInformation Display) 99 DIGEST: pp. 202-205 and Japanese PatentLaid-Open No. 202356/1999, which is incorporated herein by reference.

However, in the liquid crystal display device having this construction,the occurrence of so-called horizontal smear is visually observed on itsdisplay portion, and the occurrence of image retention is also visuallyobserved.

It has been found out that the cause of the occurrence of horizontalsmear is that the capacitance between the counter electrode formed overthe entire area of the pixel area except the periphery thereof and theplural strip-shaped pixel electrodes formed in juxtaposition on thecounter electrode with the insulating film interposed therebetweenbecomes larger than in previous type and the charge of the pixelelectrodes with signal voltages becomes insufficient, and also thevoltage of the counter electrode is distorted and the time required forthe distorted voltage to be restored to its original state becomes long.

It has also been found out that the cause of the occurrence of imageretention is that an electric field other than an electric field whichhas a component parallel to the substrate between the pixel electrodeand the counter electrode and contributes to the control of the opticaltransmissivity of the liquid crystal, i.e., an electric field having acomponent perpendicular to the substrate between the counter electrodeand the pixel electrode, is excessively strong.

SUMMARY OF THE INVENTION

The present invention has been made on the basis of the above-describedsituations, and provides a liquid crystal display device which canrestrain the occurrence of horizontal smear.

The present invention also provides a liquid crystal display devicewhich can restrain the occurrence of image retention.

A representative aspect of the invention disclosed in the presentapplication will be described below in brief.

In one embodiment, a liquid crystal display device includes a firstsubstrate. A second substrate is facing the first substrate. A liquidcrystal layer is interposed between the first and second substrates. Atleast one pixel area is defined by a plurality of gate lines and aplurality of drain lines arranged in a matrix over the first substrate,wherein the plurality of gate lines are extending in a first direction,and the plurality of drain lines are extending in a second direction. Afirst electrode is assigned to the pixel area, wherein the firstelectrode is provided over the first substrate. A second electrode isassigned to the pixel area and is facing the first electrode, whereinthe second electrode is provided over the first substrate and istransparent. The second electrode has a solid portion and a hollowportion. The hollow portion is superposed to at least a portion of thefirst electrode. An insulating layer is provided between the first andsecond electrodes.

In another embodiment, a liquid crystal display device according to thepresent invention includes a pair of substrates, a liquid crystal layerinterposed between the pair of substrates, a plurality of pixel partsbeing constructed with a plurality of gate lines and a plurality ofdrain lines arranged in a matrix on one of the pair of substrates, atleast one pair of the first electrodes and the second electrodesprovided for each pixel part between one of the pair of substrates andthe liquid crystal layer, wherein the first electrode and the secondelectrode being disposed with an insulating film interposedtherebetween, and the second electrode is transparent electrode formedin a rectangular shape and having a slit formed in a portion which issuperposed on the first electrodes.

In the liquid crystal display device constructed in this manner, theselected ones of the plural electrodes of the other electrode (forexample, pixel electrodes) are formed not to be superposed on the one ofthe pair of electrodes (for example, a counter electrode).

Accordingly, it is possible to decrease the capacitance occurringbetween the pixel electrode and the counter electrode, whereby it ispossible to restrain the occurrence of horizontal smear.

In addition, it is possible to weaken an electric field other than anelectric field which contributes to the control of the opticaltransmissivity of the liquid crystal, i.e., an electric field having acomponent perpendicular to the substrate between the counter electrodeand the pixel electrode, from among electric fields occurring betweenthe pixel electrode and the counter electrode, whereby it is possible torestrain the occurrence of image retention.

Moreover, since the holes formed in the other-side electrode aredisposed with respect to one-side electrodes that are not adjacent toone another, the holes are formed with a comparatively large space,whereby the holes have the advantage of being easily worked.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more apparent from the following detaileddescription, when taken in conjunction with the accompanying drawings,in which:

FIG. 1 is a plan view showing one embodiment of a pixel of a liquidcrystal display device according to the present invention;

FIG. 2 is a cross-sectional view taken along line 2—2 of FIG. 1;

FIG. 3 is a cross-sectional view taken along line 3—3 of FIG. 1;

FIG. 4 is a cross-sectional view take along line 4—4 of FIG. 1;

FIG. 5 is an explanatory view showing the positional relationshipbetween pixel electrodes and holes formed in a counter electrode of theliquid crystal display device according to the present invention;

FIG. 6 is a plan view showing one embodiment of the whole of the liquidcrystal display panel of the liquid crystal display device according tothe present invention;

FIG. 7 is a view showing the equivalent circuit of the liquid crystalpanel according to the present invention;

FIG. 8 is a cross-sectional view showing another embodiment of theliquid crystal display device according to the present invention; and

FIG. 9 is a plan view showing another embodiment of the liquid crystaldisplay device according to the present invention.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

Preferred embodiments of the liquid crystal display device according tothe present invention will be described below.

[Embodiment 1]

<<Construction of Pixel>>

FIG. 1 is a plan view showing the construction of a pixel area of aliquid crystal display device (panel) according to the present inventionas viewed from the liquid-crystal side of one of transparent substratesdisposed in opposition to each other with a liquid crystal interposedtherebetween.

FIG. 2 is a cross-sectional view taken along line 2—2 of FIG. 1, FIG. 3is a cross-sectional view taken along line 3—3 of FIG. 1, and FIG. 4 isa cross-sectional view take along line 4—4 of FIG. 1.

Referring first to FIG. 1, gate signal lines GL are disposed to beextended in the x-direction of FIG. 1 and to be juxtaposed in they-direction of FIG. 1, and the gate signal lines GL are formed of, forexample, chromium (Cr). These gate signal lines GL form a rectangulararea together with drain signal lines DL which will be described below,and the area constitutes a pixel area.

A counter electrode CT which generates an electric field between thecounter electrode CT and pixel electrodes PX which will be describedbelow are formed in this pixel area. This counter electrode CT is formedin the central portion of the pixel area except the periphery thereof,and is made of, for example, ITO1 (Indium-Tin-Oxide) which forms atransparent conductive layer.

As will be described later in detail, the plural pixel electrodes PX areformed in juxtaposition, and the counter electrode CT is formed in sucha manner as to be superposed on the plural pixel electrodes PX with aninsulating film GI interposed therebetween. Holes CTH are respectivelyformed in the portions of the counter electrode CT that are superposedon every other one of the pixel electrodes PX. As used herein, the term“superpose” refers a structural relationship between two materials,where one material is overlapping or vertically aligned to anothermaterial in part or in whole without regards as to which material isprovided on top. For example, the counter electrode CT, which has beendescribed above as being “superposed” to the pixel electrodes, may beprovided above the pixel electrodes or beneath the pixel electrodes,according to the definition provided herein. Similarly, the term“overlap” merely refers to describe a situation where one material isprovided over another material without making any limitation as to whichmaterial is provided on top.

A counter voltage signal line CL is formed to be connected to thecounter electrode CT in such a manner as to border the entire peripherythereof. This counter voltage signal line CL is formed integrally withcounter voltage signal lines CL which are similarly formed at therespective counter electrodes CT in the right and left pixel areas asviewed in FIG. 1 (i.e., the corresponding one of the pixel areas arrayedalong the gate signal lines GL).

In this case, the counter voltage signal lines CL are connected to oneanother at each of locations above and below the pixel areas. Thisconstruction is intended to minimize the portion of superposition ofeach of the counter voltage signal lines CL and the adjacent one of thedrain signal lines DL which will be described later, thereby reducingthe capacitance generated therebetween.

Each of these counter voltage signal lines CL is formed of an opaquematerial made of, for example, chromium (Cr). In this case, even if anelectric field which acts as noise is generated between any of the drainsignal lines DL which will be described later and the periphery of theadjacent one of the counter electrodes CT and the optical transmissivityof the liquid crystal is not obtained as desired, that portion isshielded by the counter voltage signal line CL, whereby it is possibleto solve a problem in terms of display quality.

This also means that it is possible to solve a problem due to anelectric field (noise) which is generated between any of the gate signallines GL and the periphery of the adjacent one of the counter electrodesCT.

In addition, as described above, since the material of the countervoltage signal lines CL is identical to that of the gate signal linesGL, the counter voltage signal lines CL and the gate signal lines GL canbe formed in the same process, whereby it is possible to avoid anincrease in the number of manufacturing steps.

It goes without saying that the material of the counter voltage signallines CL is not limited to Cr and the counter voltage signal lines CLmay be formed of, for example, Al or a material which contains Al.

In this case, it is effective to position the counter voltage signallines CL as a layer which overlies the counter electrodes CT. This isbecause Al is easily melted by an etching solution (for example, HBr)for selectively etching an ITO film which constitutes the counterelectrodes CT.

Furthermore, it is effective to interpose a high melting point metalsuch as Ti, Cr, Mo, Ta or W at least the interface between each of thecounter voltage signal lines CL and the adjacent one of the counterelectrodes CT. This is because ITO which constitutes the counterelectrodes CT oxidizes Al of the counter voltage signal lines CL andgenerates a high-resistance layer.

For this reason, as one example, if the counter voltage signal lines CLmade of Al or a material which contains Al are to be formed, it ispreferable to form each of the counter voltage signal lines CL as amultilayered structure having a first layer made of the high meltingpoint metal.

In this manner, the counter electrodes CT, the counter voltage signallines CL and the gate signal lines GL are formed over the transparentsubstrate, and the insulating film GI made of, for example, SiN isformed over the transparent substrate in such a manner as to cover allof the counter electrodes CT, the counter voltage signal lines CL andthe gate signal lines GL.

The insulating film GI has the function of an interlayer insulating filmfor insulating the drain signal lines DL from the counter voltage signallines CL and the gate signal lines GL. The insulating film GI also hasthe function of a gate insulating film in each area in which a thin filmtransistor TFT which will be described below is formed, as well as thefunction of a dielectric film in each area in which a capacitanceelement Cstg which will be described below is formed.

The thin film transistor TFT is formed to be superposed on a portion ofthe gate signal line GL (the bottom left portion of FIG. 1), and in thisportion, a semiconductor layer AS made of, for example, amorphoussilicon (a-Si) is formed on the insulating film GI.

A source electrode SD1 and a drain electrode SD2 are formed on the uppersurface of the semiconductor layer AS, whereby an inverted staggeredstructure MIS transistor is formed which uses a portion of the gatesignal line GL as its gate electrode. The source electrode SD1 and thedrain electrode SD2 are formed at the same time as the drain signal lineDL.

Specifically, the drain signal lines DL which are disposed to beextended in the y-direction of FIG. 1 and to be juxtaposed in thex-direction of FIG. 1 are formed, and a portion of an adjacent one ofthe drain signal lines DL is extended to the surface of thesemiconductor layer AS and constitutes the drain electrode SD2 of thethin film transistor TFT.

During the formation of the adjacent drain signal line DL, the sourceelectrode SD1 is formed, and this source electrode SD1 is extended tothe inside of the pixel area, thereby integrally forming a contactportion which provides connection between the thin film transistor TFTand the pixel electrode PX which will be described below.

As shown in FIG. 3, a contact layer d0 which is doped with, for example,an n type impurity is formed at the interface between the sourceelectrode SD1 and the drain electrode SD2 of the semiconductor layer AS.

This contact layer d0 is formed by forming an n type impurity-dopedlayer over the entire surface of the semiconductor layer AS, and, afterforming the source electrode SD1 and the drain electrode SD2, etchingthe n type impurity-doped layer on the portion of the surface of thesemiconductor layer AS that is exposed between these electrodes SD1 andSD2, by using each of these electrodes SD1 and SD2 as a mask.

In Embodiment 1, the semiconductor layer AS is formed not only in thearea in which the thin film transistor TFT is formed, but also at theintersection of the drain signal line DL and the gate signal line GL andat the intersection of the drain signal line DL and the counter voltagesignal line CL. This construction is intended to strengthen the functionof the interlayer insulating film.

A protective film PSV covers the thin film transistor TFT formed overthe surface of a transparent substrate SUB1 on which the thin filmtransistor TFT is formed. The protective film is generally made of adielectric material, for example, SiN. The protect film prevents thethin film transistor TFT from coming into direct contact with the liquidcrystal LC.

Furthermore, the pixel electrode PX which is made of a transparentconductive film are formed over the upper surface of the protective filmPSV. The pixel electrode PX is generally made of a conductive material,for example, Indium-Tin-Oxide (ITO2).

In Embodiment 1, five pixel electrodes PX are formed to be superposed onan area in which the counter electrode CT is formed, and are also formedto be extended in the y direction of FIG. 1 and to be equidistantlyspaced apart from one another. Both ends of each of the five pixelelectrodes PX are connected to the respective ends of the adjacent oneby layers made of the same material which is formed to be extended inthe x direction of FIG. 1.

In this construction, three pixel electrodes PX which are respectivelydisposed at the first, third and fifth positions as viewed from the leftside of FIG. 1 are positioned in the respective holes CTH formed in thecounter electrode CT.

Specifically, within a substantial pixel area, i.e., within the apertureof a black matrix, each of the first, third and fifth pixel electrodesPX is formed without being superposed on the counter electrode CT, andthe other pixel electrodes PX which are respectively disposed at thesecond and fourth positions as viewed from the left side of FIG. 1 areformed to be superposed on the counter electrode CT.

In the case where the pixel electrodes PX are formed in this manner,since the area of superposition of the pixel electrodes PX and thecounter electrodes CT can be decreased, the capacitance between thepixel electrodes PX and the counter electrodes CT can be decreased,whereby it is possible to decrease the occurrence of so-calledhorizontal smear.

In this construction, the holes CTH are formed in the counter electrodeCT in such a manner as to correspond to every other one of the pixelelectrodes PX. This construction is intended to facilitate the workingof the holes CTH by increasing the spaces between the adjacent holesCTH.

In Embodiment 1, the number of pixel electrodes PX per pixel area isfive, but there actually are cases in which dozens of pixel electrodesare formed per pixel area. In such a case, the holes CTH may be formedat positions which correspond to not only every other one of the pixelelectrodes PX but also every third one, every fourth one and so on,whereby it is possible to achieve far easier working of the holes CTH.

FIG. 8 is a view which shows such a construction and corresponds to FIG.2. In the construction shown in FIG. 8, the holes CTH are formed in thecounter electrode CT which underlies the juxtaposed multiple pixelelectrodes PX, at positions which correspond to every fourth one of thepixel electrodes PX.

In addition, in this embodiment, the central axis of every fourth one ofthe pixel electrodes PX agrees with that of the corresponding one of theholes CTH formed in the counter electrode CT, and each of the holes CTHis formed to have a width larger than the corresponding one of the pixelelectrodes PX.

FIG. 5 is a cross-sectional view (which corresponds to thecross-sectional view of FIG. 2) showing the positional relationshipbetween the pixel electrodes PX and the holes CTH formed in the counterelectrode CT.

As can be seen from FIG. 5, each of the counter electrodes CT which areseparated by the formation of the holes CTH (but are connected forelectrical connection at their opposite peripheral ends) is formed to besuperposed on pixel electrodes PX(2) adjacent to a pixel electrode PX(1)which is one of the pixel electrodes PX, and to be extended to the areabetween each of the pixel electrodes PX(2) and the pixel electrode PX(1)as viewed in the direction of juxtaposition of the pixel electrodes PX.Thus, each of the counter electrodes CT is formed to have an areasuperposed on the pixel electrode PX(1) and widths W.

The widths W are mainly determined from the point of view of decreasingan electric field other than an electric field which contributes to thecontrol of the optical transmissivity of the liquid crystal between thepixel electrode PX and the counter electrode CT, that is to say, anelectric field which has a component perpendicular to the substratebetween the counter electrode CT and the pixel electrode PX.Accordingly, it is appropriate to make each of the widths W smaller thanthe separation distance between the pixel electrode PX(1) and each ofthe pixel electrodes PX(2) adjacent to the pixel electrode PX(1).

The widths W are preferably as wide as possible, but slightly smallerthan the respective separation distances.

In other words, the peripheral outline portion of the counter electrodeCT has only to lie at the intermediate position between the pixelelectrode PX(1) and each of the pixel electrodes PX(2) adjacent to thepixel electrode PX(1), and the counter electrode CT has to be wider thanthe pixel electrode PX(1), preferably slightly wider.

The reason for this is that the existence of the widths W makes itpossible to strengthen an electric field having a componentapproximately parallel to the transparent substrate in each pixel areaand to decrease an electric field which occurs in a directionperpendicular to the substrate and adversely affects the phenomenon ofimage retention. In addition, as the widths W are made larger, theabsorption loss of light due to transparent electrodes becomes smallerand higher optical transmissivity can be obtained.

The bottom-end same-material layer of each of the pixel electrodes PXwhich are formed in this manner is connected to a contact portion of thesource electrode SD1 of the thin film transistor TFT through a contacthole formed in the protective film PSV. The top-end same-material layeris formed to be superposed on the counter voltage signal line CL.

In the case of this construction, a capacitance element Cstg which usesas a dielectric film a stacked film made of the insulating film GI andthe protective film PSV is formed in the portion of superposition of thecounter electrode CT and each of the pixel electrodes PX.

This capacitance element Cstg is formed for purposes such as storing avideo signal in the pixel electrode PX for a comparatively long periodeven if the thin film transistor TFT is turned off after the videosignal from the drain signal line DL is applied to the pixel electrodePX via the thin film transistor TFT.

An alignment film ORI1 which covers the pixel electrodes PX is formedover the surface of the transparent substrate SUB1 over which the pixelelectrodes PX are formed in the above-described manner. This alignmentfilm ORI1 is a film which is in direct contact with the liquid crystalLC and determines the initial alignment direction of the liquid crystalLC.

Incidentally, in Embodiment 1, the initial alignment direction is made75° with respect to the direction of application of an electric field.The initial alignment direction is not limited to 75°, and may begreater than 0° and less than 90° , preferably 10° to 80° so thathigh-speed responses (drivable at low voltages) can be achieved.

In the above-described embodiment, the gate signal lines GL, the countervoltage signal lines CL and the drain signal lines DL are formed ofchromium (Cr). However, it goes without saying that another high meltingpoint metal such as Mo, W, Ti or Ta or an alloy of two or more kinds ofsuch metals or a stacked film made of two or more kinds of such metalsmay also be used.

Moreover, although in the above description the transparent conductivefilm is made of ITO, it goes without saying that similar advantages canbe obtained even with IZO (Indium-Zinc-Oxide).

The transparent substrate constructed in this manner is called a TFTsubstrate, and a transparent substrate disposed in opposition to thisTFT substrate with the liquid crystal LC interposed therebetween iscalled a filter substrate.

<<Filter Substrate>>

As shown in FIG. 2, on the liquid crystal-side surface of the filtersubstrate, a black matrix BM is formed to separate the pixel areas fromone another, and a filter FIL is formed to cover each aperture of theblack matrix BM that determines a substantial pixel area.

An overcoat layer OC made of, for example, a resin layer is formed tocover the black matrix BM and the filter FIL, and an alignment layerORI2 is formed on the overcoat layer OC.

The alignment direction of the alignment layer ORI2 is selected to bethe same as that of the alignment film ORI1 when the alignment film ORI1is superposed on the alignment layer ORI1. That is to say, the alignmentof the molecules of the liquid crystal LC is made homogeneous.

<<Liquid Crystal Layer>>

In Embodiment 1, a liquid crystal having a dielectric anisotropy Δε of,for example, −5 is used, whereby it is possible to obtain a high opticaltransmissivity. This is because the directors of the liquid crystalmolecules of a liquid crystal of negative Δε do not greatly change dueto an electric-field component perpendicular to a substrate surface.

Embodiment 1 uses a liquid crystal of negative Δε, but even if a liquidcrystal of positive Δε is used, the effects and advantages of thepresent invention can similarly be obtained.

Since the liquid crystal of positive Δε is large in Δε and low inviscosity compared to the liquid crystal of negative Δε, the liquidcrystal of positive Δε has the advantage of being drivable at lowervoltages and at higher response speeds.

<<Entire Construction of Liquid Crystal Display Panel>>

FIG. 6 is a view of the entire construction of the liquid crystaldisplay panel, showing a display area AR constructed of an assembly ofpixel areas arranged in matrix form.

A transparent substrate SUB2 is formed to be slightly smaller than thetransparent substrate SUB1, and the right and bottom sides (as viewed inFIG. 6) of the transparent substrate SUB2 are disposed to beapproximately in flush with the corresponding sides of the transparentsubstrate SUB1.

Accordingly, areas which are not covered with the transparent substrateSUB2 are respectively formed along the left and top sides (as viewed inFIG. 5) of the transparent substrate SUB1, and gate signal terminals Tgand drain signal terminals Td are formed in the respect areas. The gatesignal terminals Tg are formed for supplying scanning signals to therespective gate signal lines GL, while the drain signal terminals Td areformed for supplying video signals to the respective drain signal linesDL.

The transparent substrate SUB2 is secured to the transparent substrateSUB1 by a sealing material SL formed along the periphery of thetransparent substrate SUB2, and this sealing material SL also has thefunction of a sealing material for sealing the liquid crystal LC betweenthe transparent substrates SUB1 and SUB2.

A liquid crystal filling port INJ is disposed in a portion of thesealing material SL, and after the gap between the transparentsubstrates SUB1 and SUB2 has been filled with the liquid crystal LCthrough the liquid crystal filling port INJ, the liquid crystal fillingport INJ is sealed by a liquid crystal sealing material (not shown).

Polarizers are respectively stuck to the outside surfaces of thetransparent substrates SUB1 and SUB2 in such a manner that thetransparent substrates SUB1 and SUB2 are interposed between thepolarizers.

<<Equivalent Circuit>>

FIG. 7 is a view showing the equivalent circuit of the liquid crystalpanel as well as the external circuits of the liquid crystal panel.

Scanning signals (voltage signals) are sequentially supplied to theindividual gate signal lines GL disposed to be extended in thex-direction of FIG. 7 and to be juxtaposed in the y-direction of FIG. 7,by a vertical scanning circuit V.

The thin film transistors TFT in the respective pixel areas arrangedalong the one of the gate signal lines GL to which a scanning signal issupplied are turned on by the scanning signal.

At this timing, video signals are supplied to the individual drainsignal lines DL from a video signal driver circuit H, and these videosignals are applied to the respective pixel electrodes PX via the thinfilm transistors of the corresponding pixel areas.

In the respective pixel areas, counter voltages are applied to thecounter electrodes CT formed together with the pixel electrodes PX viathe counter voltage signal lines CL, so that electric fields can begenerated between the pixel electrodes and the counter electrodes CT.

The optical transmissivity of the liquid crystal LC is controlled by theones (in-plane electric fields) of these electric fields each of whichhas a component parallel to the transparent substrate SUB1.

Incidentally, in FIG. 7, the symbols R, G and B shown in the individualpixel areas represent that a red filter, a green filter and a bluefilter are formed in the respective pixel areas.

<<Other Embodiments>>

In the above-described embodiment, the counter electrodes CT are formedbelow the pixel electrodes PX with the insulating film GI interposedtherebetween. However, the present invention is not limited to thisconstruction, and it goes without saying that the pixel electrodes PXare formed below the counter electrodes CT with the insulating film GIinterposed therebetween.

In the above-described embodiment, the pixel electrodes PX formed injuxtaposition are formed as rectilinear strip-shaped electrodes in therespective pixel areas.

However, the present invention is not limited to this construction, andit goes without saying that each of the pixel electrodes PX may be anelement having one or more bent portions in the direction of extensionof the pixel electrode PX.

Such an electrode is called a multi domain scheme in which the directionof an electric field generated between the electrode and the counterelectrode CT is made different to provide the advantage of canceling adifference in the optical transmissivity of a liquid crystal when adisplay area is viewed in any direction different from the directionnormal to its front surface.

Even in this case, the holes CTH can be formed in the counter electrodeCT at locations corresponding to the bent extended portion of the pixelelectrode PX.

FIG. 9 is a plan view which corresponds to FIG. 1, showing an example towhich the multi domain scheme is applied.

Each of the pixel electrodes PX has, for example, a zigzag pattern alongits extension direction, and the holes CTH each having a zigzag shapealong the zigzag pattern are respectively formed in the counterelectrodes CT which are superposed on some of the pixel electrodes PX(for example, every other one of the pixel electrodes PX).

The extension direction of the pixel electrodes PX is along they-direction of FIG. 9, but the present invention is not limited to thisconstruction and can, of course, be applied to a construction in whichthe extension direction of the pixel electrodes PX is along thex-direction of FIG. 9.

In the above-described embodiment, an electrode which is formed overnearly the whole of the central portion of the pixel area except theperiphery thereof serves as the counter electrode CT, while pluralstrip-shaped electrodes which are juxtaposed in one direction serve asthe pixel electrodes PX. However, an electrode which is formed over thecentral portion of the pixel area except the periphery thereof may beused as the pixel electrode PX, while plural strip-shaped electrodeswhich are juxtaposed in one direction may be used as the counterelectrode CT.

As is apparent from the foregoing description, in accordance with theliquid crystal display device according to the present invention, it ispossible to prevent the occurrence of horizontal smear and imageretention.

What is claimed is:
 1. A liquid crystal display device comprising: firstand second substrates with a liquid crystal layer provided therebetween;a plurality of gate lines and a plurality of drain lines provided on thefirst substrate; a plurality of pixel regions defined by the gate linesand drain lines; a plurality of first electrodes being provided withinat least one of the pixel regions, the first electrodes beingsubstantially parallel to each other, wherein the adjacent firstelectrodes are spaced apart and define a space therebetween, the firstelectrodes being wider than the space; a plurality of second electrodesbeing provided within the at least one pixel region, wherein at leastone of the second electrodes is vertically aligned to the space definedby the adjacent first electrodes; and an insulating layer providedbetween the first and second electrodes.
 2. The liquid crystal displaydevice according to claim 1, wherein the first electrodes aresubstantially to the second electrodes.
 3. The liquid crystal displaydevice according to claim 2, further comprising: a first connectingmember coupled to the plurality of first electrodes; a second connectingmember coupled to the plurality of second electrodes; and an insulatinglayer provided between the first connecting member and the secondconnecting member.
 4. The liquid crystal display device according toclaim 3, wherein the plurality of first electrodes and the plurality ofsecond electrodes have a zigzag pattern.
 5. The liquid crystal displaydevice according to claim 2, wherein each pixel region includes theplurality of first electrodes and the plurality of second electrodesprovided therein and one or more of the second electrodes are verticallyaligned to the first electrodes, wherein a number of the secondelectrodes being vertically aligned to the first electrodes is greaterthan a number of the second electrodes being vertically aligned to thespaces.
 6. The liquid crystal display device according to claim 2,wherein the first electrodes are counter electrodes and the secondelectrodes are pixel electrodes.
 7. The liquid crystal display deviceaccording to claim 6, wherein at least one of the first electrodesincludes overlapping portion with a counter voltage signal line.
 8. Theliquid crystal display device according to claim 2, wherein thesecond-electrodes are transparent conductive material.
 9. The liquidcrystal display device according to claim 8, wherein the firstelectrodes are transparent conductive material.
 10. The liquid crystaldisplay device according to claim 1, further comprising: a firstconnecting member coupled to the plurality of first electrodes; a secondconnecting member coupled to the plurality of second electrodes; and aninsulating layer provided between the first connecting member and thesecond connecting member.
 11. The liquid crystal display deviceaccording to claim 10, wherein the plurality of first electrodes and theplurality of second electrodes have a zigzag pattern.
 12. The liquidcrystal display device according to claim 10, wherein each pixel regionincludes the plurality of first electrodes and the plurality of secondelectrodes provided therein and one or more of the second electrodes arevertically aligned to the first electrodes, wherein a number of thesecond electrodes being vertically aligned to the first electrodes isgreater than a number of the second electrodes being vertically alignedto the spaces.
 13. The liquid crystal display device according to claim10, wherein the first electrodes are counter electrodes the secondelectrodes are pixel electrodes.
 14. The liquid crystal display deviceaccording to claim 10, wherein the second electrodes are transparent dconductive material.
 15. The liquid crystal display device according toclaim 14, where the first electrodes are transparent and conductivematerial.
 16. The liquid crystal display device according to claim 15,wherein at least one of the first electrodes includes overlappingportion with a counter voltage signal line.
 17. A liquid crystal displaydevice comprising: first and second substrates with a liquid crystallayer provided therebetween; a plurality of gate lines and a pluralityof drain lines formed on the first substrate; a pixel region defined byadjacent gate lines and drain lines; and a plurality of first electrodesand a plurality of second electrode provided within the pixel region onthe first substrate, the first electrodes and second electrodes beingtransparent and conductive material, wherein at least two opposing edgesof one of the first electrodes are covered by opaque material.
 18. Theliquid crystal display device according to claim 17, wherein the firstelectrodes are counter electrodes, he second electrodes are pixelelectrodes, and the opaque material is a counter voltage signal line.19. The liquid crystal display device according to claim 17, wherein theone of the first electrodes and the opaque material is electricallycoupled.
 20. The liquid crystal display device according to claim 17,wherein the opaque material is formed on the one of the firstelectrodes.
 21. The liquid crystal display device according to claim 17,wherein the plurality of first electrodes and the plurality of secondelectrodes are provided in a zigzag pattern.
 22. The liquid crystaldisplay device according to claim 17, wherein the plurality of firstelectrodes are arranged substantially parallel and spaced apart fromeach other to define a space between two adjacent first electrodes, afirst set of the second electrodes directly overlying the space and asecond set of the second electrodes directly overlying one or more ofthe first electrodes, the first electrode being wider than the space,wherein an insulating layer is provided between the first and secondelectrodes.
 23. The liquid crystal display device according to claim 22,wherein a number of the second electrodes in the second set is greaterthan a number of the second electrodes in the first set.
 24. The liquidcrystal display device according to claim 17, wherein an edge of atleast one of the second electrodes includes an portion that overlapswith the opaque material, where an insulating layer is providedtherebetween.